The present invention relates generally to air data sensing systems for use on an air vehicle. More particularly, the present invention relates to multi-function air data probes employed in an air data sensing system.
Air data systems that calculate the aerodynamic aircraft angle of attack (AOA) and angle of sideslip (AOS) of an air vehicle utilizing independent probes that are not pneumatically coupled, but which have processors for interchanging electrical signals between the probes, are known in the art. These probes are sometimes referred to as multi-function probes (MFPs). MFPs include processing circuitry located at the probe itself as part of its instrument package. With the help of the processing circuitry, MFPs are capable of converting pressure, measured by sensors included in the MFPs, into various useful local (to the probes) parameters, such as local AOA α1, local Mach number M1 and local static pressure Ps1. These local parameters are utilized for the determination of aircraft AOA, aircraft AOS and other aircraft parameters including determination of altitude from static pressure or other means.
One current technique, used with MFPs, for determining the above-mentioned local parameters includes employing a multiple table lookup and interpolation scheme. Although this technique produces relatively accurate results, it is slow, requires the use of a relatively large amount of memory and is costly to implement. Further, it demonstrates a substantial degradation in performance when there are relatively large variations in the input measured pressure. Other current techniques likewise suffer from several of the above-mentioned disadvantages. Consequently, a faster, less expensive technique for determining local air data parameters, which can produce more robust results from noisy input data, would be a significant improvement in the art.